The present invention relates to a semiconductor device having a plurality of semiconductor chips such as a computer, a semiconductor image sensor device and the like, and particularly to a semiconductor image sensor device utilized for detecting not only visible light, infrared rays and ultraviolet rays, but also X-rays, radioactive rays and charged particles. The semiconductor image sensor device refers to various semiconductor integrated circuit devices including photodiodes, photodiode arrays, photosensors, microstrip sensors, two-face microstrip sensors, radioactive sensors, semiconductor photosensors, and semiconductor imaging devices. The term "detecting" means production of a signal upon receiving of such an light rays and radioactive rays. An element or a portion of a detection area is referred to as a "photosensor" or "light receiving area". Further, the term "image sensor device" refers to a device composed of an arrangement of photosensors for producing two-dimensional image information according to detected signals from the photosensors. Such a type of device may be composed of a single photosensor chip for performing a certain function. However, the present invention particularly relates to a specific construction of the type composed of a plurality of sensor chips mechanically and electrically integrated with each other to function as the semiconductor image sensor device, as a whole. Hereinafter, such an integrated construction will be referred to as a "semiconductor image sensor device of the multiple chip mount type".
FIGS. 41 and 42 show such a type of conventional structure. In the prior art, as shown in FIG. 41, the sensor device is comprised of four pieces of semiconductor image sensor chips 1, and two pieces of driver substrates 3 for controlling the sensor chips 1 to retrieve a signal. As shown in FIG. 42, these sensor chips 1 and driver substrates 3 are united with each other at the bottom by means of a one piece support member 76. In this conventional structure, electrical connection is provided by means of bonding wires 73 among the semiconductor image sensor chips 1 and driver substrates 3. In addition, each sensor chip 1 is formed with sensing lines 5 and corresponding pad electrodes 75 for wire bonding. Each driver substrate 3 is provided with a semiconductor driving chip 2 and pad electrodes 74 for wire bonding. Though not shown in the figures, the driving chip 2 and the driver substrate 3 are wire-bonded.
Though FIG. 41 is illustratively simplified for facilitating understanding, actually, the semiconductor image sensor chip 1 has a size much greater than an ordinary semiconductor chip. For example, the sensor chip 1 has a length of 5-7 cm along the sensing line 5 and a width of 3 cm. The sensor chip 1 practically contains about 600 sensing lines 5 (only 6 of the sensing lines 5 are illustrated in FIG. 41) aligned at a pitch of about 50 .mu.m. Thus, the FIG. 41 device has an entire length of 30 cm and a width of 3 cm.
As mentioned above, in the conventional semiconductor image sensor device of the multiple chip mount type, separate means are provided at the top and bottom sides for mechanical unification of the multiple chips and circuit substrates with each other, and for electrical connection to constitute a system. Such a construction raises the following various drawbacks. First, a mechanical support structure is necessarily required. Second, the mechanical support structure may affect the light receiving area to hinder the detection efficiency. Third, both mechanical coupling work and electrical connection work are needed to thereby prolong assembling time. Fourth, the electrical connection work by wire bonding may not be well conducted if the pad electrodes have an excessively narrow-pitch. Namely, during the wire bonding operation, an already coupled wire might be broken by a bonding tool. Fifth, even if the bonding operation is finished safely, inadvertent external force might be incidentally applied so that a wire is broken, or is contacted to an adjacent wire to cause a short circuit defect. Sixth, the mechanical rigidity solely depends on the support structure, thereby causing restriction of shaping and positioning of the support member.
Further, the internal pattern arrangement is restricted in the semiconductor driving chip 2 because of the need to leave a space for wire bonding. Namely, the driving chip 2 is provided with input terminals corresponding to each of the sensing lines or strip lines which are arranged at a close pitch with each other. Therefore, the pitch of the adjacent input terminals is also made close. In such a case, there could not be provided a sufficient space for forming an input single processing circuit (input buffer) which is located in the vicinity of the input terminals. Consequently, it is practically difficult to reduce the pitch of the input terminal arrangement.